I used to be told by a couple of friends in high school that they thought I was "innocent" all because I was just a friendly person. Once they got to know me and I started swearing/saying stuff that would be considered "outside my bubble", they were surprised lol.
Another one was someone thought I was the theater/band type but I've never shown interest in those sorts of extra curriculars, nor did I consider myself to be artistic and I've only done a couple sports since I preferred more athletic activities.
I remember saying one time that my favorite kind of music was rock, and someone stated that they thought I would be into country, which I don't know what that's supposed to mean because there's nothing country about me at all lol. But I've also been called "emo" before because of my music taste and how I would dress "edgy" like wearing hot topic shirts, black skinny jeans, leather jackets, converse/heeled boots, studded belts, etc. I don't have a label; it's just who I am. My wardrobe is pretty diverse.
Thought I'd list a few of my own but I'm interested to know what assumptions people have made about you, whether you took offense to it or not.